1. Field of the Invention
This invention relates to a method and kit apparatus for custom manufacturing O-rings from cord stock materials.
2. Description of the Prior Art
There are several apparatuses available for the manufacture of O-rings. For example, there is an "O-Ring Splicing Kit 112" available from the Loctite Corporation of Newington, Conn. That kit is specifically adapted to form O-rings from material such as Buna-N rubber cord. A cord is first placed in a "Loctite.RTM. O-ring splicing fixture" and then cut to the proper length. The splicing fixture is disclosed in U.S. Pat. No. 3,341,870 and U.S. Design Pat. No. 206,551. A thin film of "Loctite quick-set adhesive 404" is then applied to one end of the rubber cord and then the two ends are joined in a special groove in the splicing fixture where they are allowed to set under a small amount of finger pressure. The O-rings formed in that manner are satisfactory for some applications, especially where heat is not a problem. It is believed that the Buna-N rubber is satisfactory for temperatures up to approximately 250.degree. F. For higher temperatures industry frequently uses Viton.RTM. O-rings. Viton.RTM. is a registered trademark of the DuPont Corporation of Wilmington, Del. Viton.RTM. is believed to be acceptable for temperatures in the range of approximately 450.degree.. However, it is difficult to custom form Viton.RTM. in view of the fact that it must be vulcanized. One of the primary purposes of Applicant's invention is to provide a portable device that will allow users to form custom made O-rings from high temperature resistant material such as Viton.RTM..
A "Method of Fabricating O-Rings" is disclosed in U.S. Pat. No. 3,026,569 to Keller. The method disclosed therein includes the steps of severing a piece of extruded uncured elastomer to a length slightly larger than the circumference of the ultimate O-ring, overlapping the materials and then causing the O-ring to cure in a special mold. The Keller method also specifically discloses the use of a heating mechanism in FIG. 13 thereof which is employed to assist in the vulcanization of the materials.
Another U.S. Pat. No. 3,107,393 to the same inventor discloses a more conventional prior art apparatus and method for fabricating O-rings.
The Sivon Manufacturing Company, Inc. of Perry, Ohio manufactures a customized vulcanizer which can be used to produce O-rings with different characteristics. The device is advertized and sold as a SMACO Model 50 Vulcanizer and can be operated either manually or by a foot pedal. The device apparently can perform the tasks of splicing and embossing as well as vulcanizing. It is noted, however, that the Sivon Vulcanizer is considerably more complicated and bulky than the present invention which is directed more toward emergency situations.
There are many different methods and apparatus for fusing plastic-like materials. See for example, Kenyon, U.S. Pat. No. 2,765,837, Butler U.S. Pat. No. 2,521,282; and Grotten et al U.S. Pat. No. 2,514,197 which disclose prior art methods for fusing such materials under conditions of elevated temperature and pressure. Similar methods are known in the automobile tire manufacturing art. See for example, Ludington, U.S. Pat. No. 754,078 and Loomis, U.S. Pat. No. 2,688,996.
The molding of "gasketing material" into a helical shape is disclosed in U.S. Pat. No. 3,406,430 to Furstenburg et al.
The use of insertable heating elements is known in some arts. For example, Howard, U.S. Pat. No. 3,799,727 discloses a heating mechanism in which the heating elements are adapted to slide in and out of the heating area. The use of an electrical control mechanism for heating elements is also known to those of skill in the art and disclosed in U.S. Pat. No. 3,799,727.
Devices for making diagonal cuts through materials have been known for many years. Miter boxes have been used extensively for the purpose of making diagonal cuts through wood and similar materials. U.S. Pat. No. 3,811,356 to Wyler discloses a "Miter Box of Variable Width". It is similar in a very limited respect to Applicant's cord holding fixture in that the distance between the guides can be adjusted to accomodate materials of different widths. Adjustment in the Wyler device is accomplished in finite steps by placing or removing spacers between the saw guides.
There are several devices available on the market that are suitable for the cutting of O-ring cord stock. For example, the Sivon Manufacturing Co., Inc. of Perry, Ohio manufactures three straight blade cutters for use on cord stocks of Buna-N, Neoprene, Silicone and Viton.RTM.. The three cutters include the "SMACO" Cantilever Cutter, the "SMACO" Pivot Cutter and the "SMACO" Automatic Guillotine Cutter. The foregoing devices are believed to be more complicated and bulky than the cord cutter of the present invention. In addition, guillotine type cutters are dangerous and inadequate for the purpose of marking two diagonal mating cuts simultaneously. It would probably take at least two people to safely make diagonal cuts--one to hold the ends of the cord and one to operate the machine.